US3090009A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Noise figure improvement in radio receivers
Assignee: AT&T Inc
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Filing: 1958-12-30
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Granted: 1963-05-14
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Expires: 1978-12-30
Abstract
No abstract record available.
Inventors
- 👤 Rudolf S Engelbrecht
- 👤 William W Mumford
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 15:43
CPC Classifications
H; H03; H03F; H03F1/00; H03F1/26; H03F1/28
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
149 words
IN A RADIO RECEIVER, AN ANTENNA CIRCUIT, A FREQUENCY CONVERTER HAVING BILATERAL TRANSMISSION, TRANSMISSION MEANS INTERCONNECTING SAID ANTENNA CIRCUIT AND SAID CONVERTER, SAID ANTENNA CIRCUIT, TRANSMISSION MEANS, AND COVERTER, RESPECTIVELY, HAVING IMPEDANCES WHICH, TAKEN ALONE, PROVIDE FOR MAXIMUM POWER TRANSFER BETWEEN SAID ANTENNA CIRCUIT AND SAID CONVERTER, AND MEANS FOR MINIMIZING THE EFFECT OF CIRCUIT NOISE ORIGINATING AT THE OUTPUT OF SAID CONVERTER, COMPRISING AN IMPEDANCE MISMATCH POSITIONED IN SAID TRANSMISSION MEANS TO REFLECT NOISE ORIGINATING AT THE OUTPUT OF SAID CONVERTER AND TRAVELING TOWARD SAID ANTENNA CIRCUIT, BACK TO THE OUTPUT OF SAID CONVERTER 180* OUT OF PHASE AT THE INPUT SIGNAL FREQUENCY WITH THE NOISE ORIGINATING AT SAID OUTPUT, THE DEGREE OF MISMATCH INTRODUCED BEING EFFECTIVE TO CAUSE A GREATER REDUCTION IN THE NOISE AT THE OUTPUT OF SAID CONVERTER THAN THE REDUCTION IN POWER TRANSFER OF THE INPUT SIGNAL BETWEEN SAID ANTENNA CIRCUIT AND SAID CONVERTER.
Claim 2
Dependent Claim
149 words
IN A RADIO RECEIVER, AN ANTENNA CIRCUIT, A FREQUENCY CONVERTER HAVING BILATERAL TRANSMISSION, TRANSMISSION MEANS INTERCONNECTING SAID ANTENNA CIRCUIT AND SAID CONVERTER, SAID ANTENNA CIRCUIT, TRANSMISSION MEANS, AND COVERTER, RESPECTIVELY, HAVING IMPEDANCES WHICH, TAKEN ALONE, PROVIDE FOR MAXIMUM POWER TRANSFER BETWEEN SAID ANTENNA CIRCUIT AND SAID CONVERTER, AND MEANS FOR MINIMIZING THE EFFECT OF CIRCUIT NOISE ORIGINATING AT THE OUTPUT OF SAID CONVERTER, COMPRISING AN IMPEDANCE MISMATCH POSITIONED IN SAID TRANSMISSION MEANS TO REFLECT NOISE ORIGINATING AT THE OUTPUT OF SAID CONVERTER AND TRAVELING TOWARD SAID ANTENNA CIRCUIT, BACK TO THE OUTPUT OF SAID CONVERTER 180* OUT OF PHASE AT THE INPUT SIGNAL FREQUENCY WITH THE NOISE ORIGINATING AT SAID OUTPUT, THE DEGREE OF MISMATCH INTRODUCED BEING EFFECTIVE TO CAUSE A GREATER REDUCTION IN THE NOISE AT THE OUTPUT OF SAID CONVERTER THAN THE REDUCTION IN POWER TRANSFER OF THE INPUT SIGNAL BETWEEN SAID ANTENNA CIRCUIT AND SAID CONVERTER.
References Cited (Backward Citations)
GB467332A
Cited
US2753526A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1966-05-13 | 1966-11-12 | 1967-05-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1970-05-13 | 1970-11-12 | 1971-05-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1974-05-13 | 1974-11-12 | 1975-05-14 | $7700.00 | Window Closed / Lapsed |